MUSKEGON, Mich. – As publicity into the mysterious disappearance of Jessica Heeringa began to dominate headlines more than five years ago, Norton Shores police found themselves inundated with tips.

More than 2,000 tips were received and vetted, the lead detective testified Tuesday in the trial of 48-year-old Jeffrey Willis, who is accused in the abduction and murder of the 25-year-old mother of one.

"I didn't know how big it was going to get," Norton Shores Police Lt. Michael Kasher testified.

The intensely-watched trial, which got underway last week, is winding down and could go to jurors on Wednesday.

Six witnesses testified on Tuesday, including Kasher. He was the last to testify before Muskegon County Circuit Court Judge William Marietti ended the days’ proceedings at 4 p.m. because a juror became ill.

Read more: Blog from Tuesday's testimony

Kasher took the stand around 2:30 p.m. and addressed several aspects of the investigation that came under scrutiny, including how it was handled starting about a half-hour after Heeringa went missing on April 26, 2013.

"I didn't know how big it was going to get," Kasher said.

Kasher testified that by 6 a.m. on April 27, 2013, he realized that something serious had happened. By midday, 20 or so people from Michigan State Police and the Muskegon County Sheriff's Department were helping out, he said.

The Norton Shores Police Department tip line was inundated days after Heeringa's disappearance; Kasher said they had to rely on a different state police computer system to help keep pace.

Around 2,200 tips were logged; Kasher said police worked to investigate each of them. Each tip received was assigned a number and was rated on its level of importance before being assigned to an officer.

By September, most of the assisting officers had to return to their own departments. Kasher testified that he remained dedicated to the case. He said of the hundreds of people interviewed, only 27 provided any sort of lead.

When the department first identified the vehicle in question as a silver minivan, Kasher said the make and model did not matter.

"If anyone wants to blame the Town & Country thing on someone, you can blame it on me," Kasher said. "I didn't know a lot about vans; I was just trying to put a timeline together."

Norton Shores Police were initially looking for a silver Chrysler Town & Country, which they later determined was actually a Dodge Grand Caravan. That determination was made with the assistance of experts, including Lawrence Brooks of Chrysler-Fiat, who testified on Tuesday.

The change in the vehicle description raised questions in the minds of the public at the time, according to testimony.

Read more: 15,000 videos of local girls at swim meets found on Jeffrey Willis' computer

Ryan Heethuis, a U.S. Secret Service agent, who assisted with both the Heeringa and Bletsch investigations testified as well. Heethuis said he runs a 'Proof of Life' test through their systems looking for signs of Heeringa to this day.

United States Secret Service Investigative Analyst Ryan Heethuis testifies on Tuesday, May 15, 2018 in the 14th Judicial Circuit Court in Muskegon, Michigan. Jeffrey Willis is facing trial for the kidnapping and murder of Heeringa.
United States Secret Service Investigative Analyst Ryan Heethuis testifies on Tuesday, May 15, 2018 in the 14th Judicial Circuit Court in Muskegon, Michigan. Jeffrey Willis is facing trial for the kidnapping and murder of Heeringa.
Mike Krebs | MLive.com

During every cross examination, defense attorney Fred Johnson turned to Willis in between questions. As he has throughout most days of testimony, Willis listened intently, often leaning into the witness, his hand switching between a highlighter and a pen as he took to his notes and documents. His demeanor remained light throughout the day, laughing when a joke was made and smirking at his attorney in between whispers.

Jeffrey Willis speaks with his attorney on Tuesday, May 15, 2018 in the 14th Judicial Circuit Court in Muskegon, Michigan. Willis is facing trial for the kidnapping and murder of Heeringa. Her body has never been recovered.
Jeffrey Willis speaks with his attorney on Tuesday, May 15, 2018 in the 14th Judicial Circuit Court in Muskegon, Michigan. Willis is facing trial for the kidnapping and murder of Heeringa. Her body has never been recovered.
Mike Krebs | MLive.com

When Michigan State Police Detective Zachary Sparks took the stand to testify about evidence collected during a search warrant, it appeared to be Willis directing the questions. Sparks testified that he found nearly a dozen different emptied bleach products in the basement of Willis' late grandfather's home at 3038 Bailey Street. Also found at the home, primarily used by Willis after his grandfather's passing, was a list including clothing items, but also, zip ties, lube and needles.

An evidence photo of cleaning supplies found in the house of Jeffrey Willis's late-grandfather is presented in court on Tuesday, May 15, 2018 in the 14th Judicial Circuit Court in Muskegon, Michigan.
An evidence photo of cleaning supplies found in the house of Jeffrey Willis's late-grandfather is presented in court on Tuesday, May 15, 2018 in the 14th Judicial Circuit Court in Muskegon, Michigan.
Mike Krebs | MLive.com

In cross examination, Johnson consulted Willis before asking if it was possible this list was just a packing list for one of Willis' snowmobiling trips, providing the idea that the lube was actually lube for a snowmobile.

Michigan State Police Sgt. Zachary Sparks presents a note he found at the home of Jeffrey Willis's late grandfather while completing a search warrant on Tuesday, May 15, 2018 in the 14th Judicial Circuit Court in Muskegon, Michigan.
Michigan State Police Sgt. Zachary Sparks presents a note he found at the home of Jeffrey Willis's late grandfather while completing a search warrant on Tuesday, May 15, 2018 in the 14th Judicial Circuit Court in Muskegon, Michigan.
Mike Krebs | MLive.com

It's been a peculiar trial - namely due to the fact that Jessica Heeringa's body is still missing and her family remains absent from the courtroom. Meanwhile, the family has continued to vocalize their opinion via a public Facebook page dedicated to finding Jessica. Friends of the family say the only thing that will bring them closure is finding her.

Court will reconvene at 10 a.m. on Wednesday.

Recording of Monday's proceedings

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Emma Nicolas is a multimedia journalist. Have a news tip or question for Emma? Get in touch by email enicolas@wzzm13.com, Facebook or Twitter.